Mason, 49, who helped persuade a local priest to protest diocesan financial support of accused clergy, has denounced the church's reaction to the scandal in letters and opinion pieces in various publications. He also has been a source for newspaper articles that have appeared in newspapers ranging from The Republican to USA Today.

Now Mason, a salesman who also has marketing experience, is the subject of controversy himself, accused of posing as a reporter to obtain information. The issue also has raised questions about his working relationship with the lead reporter for The Republican's groundbreaking coverage of the church scandal.

The controversy, which was the subject of an article in this week's Catholic Observer, arose last month when a spokesman for the Roman Catholic Diocese in Charlotte, N.C., said that Mason had represented himself as a writer for The Republican and a collaborator on a book with reporter William Zajac on the Springfield clergy abuse scandal.

When Marie P. Grady, managing editor of The Republican, learned about the controversy from the Springfield Diocese, she told spokesmen for both dioceses that Mason had no working relationship with the newspaper and she had no knowledge of a book project involving him and Zajac.

Grady said that several months ago Zajac raised the possibility of writing a book someday, but in the absence of a detailed proposal she had neither raised objections nor given final approval. She said she told Zajac at the time that if any book ever were to be written, the paper's resources and role in uncovering the scandal would have to be credited.

After she told Zajac of the Charlotte accusations, Grady said Zajac told her he had discussed with Mason the idea of writing a book, and Mason had helped to market the idea. Zajac said the idea, which he described as being in its early stages, was later abandoned.

Grady said the case has prompted the newspaper to reiterate to its staff a long-standing policy that any work done outside the newspaper must be approved in advance by the executive editor and publisher. Grady said the policy guards against not only conflict but also the appearance of conflict.

"Bill Zajac has built up a tremendous reputation for integrity and credibility, both among alleged victims and clergy, following more than two years of reporting on the tragedy of clergy sexual abuse," Grady said, pointing to Zajac's work on a story that ultimately led to the resignation of former Bishop Thomas L. Dupre amid sexual abuse allegations.

"It would be unfortunate if these allegations, as well as any ill-conceived discussion about a book collaboration, served to undermine the work of those who help to uncover the problem of abuse, including both victims and activists."

Mason, a member of St. Michael's Parish in East Longmeadow, assailed the Catholic Observer story, which carried the byline of the Rev. William A. Pomerleau, as an effort to besmirch Zajac and The Republican for coverage of the abuse scandal.

"They'd like to shoot the messenger," Mason said.

Pomerleau rebutted the allegation, saying his story wasn't about Zajac and his work.

"The story is about Mr. Mason misrepresenting himself as a journalist," he said.

Mason denied Friday that he ever identified himself to two North Carolina dioceses, including the Raleigh Diocese, as working for The Republican. But he said it could have been misconstrued that way.

Mason said he identified himself as a freelance journalist, who wrote op-ed articles, and as someone working on a book with Zajac, a reporter for The Republican. He said he also noted that Zajac, who was on vacation at the time, was working on an article for the newspaper about a former North Carolina priest, now living in Palmer.

The Oct. 11 article concerned a local man's unsuccessful effort to have Springfield diocesan officials warn parishioners of the priest, who had been convicted of child molestation in North Carolina. The priest was not an employee of the Springfield Diocese.

Zajac said Friday he had spoken with Mason after Grady told him of the allegations.

"He seemed to make an admission that he did misrepresent himself," Zajac said. "There was certainly no denial about it."

Zajac and Mason each said their reporter-source relationship remains intact and amicable. Each also said the book idea is dead.

Mason said the focus of the book was going to be the overall problem of clergy abuse in this region and the efforts to fight it by the Rev. James J. Scahill, an East Longmeadow pastor, who has been critical of the diocese's handling of abuse allegations. Scahill, with the urging of Mason, led his parish in a protest against church policy on sexual abuse that involved withholding collection money earmarked for the diocese.

Mason said he and Zajac had floated inquiries to literary agents and editors about the book project, as well as written summaries and a preliminary chapter. He said he and Zajac had received mixed response to the inquiries.

Michael Parks, director of the University of Southern California's Annenberg School of Journalism and a former editor of the Los Angeles Times, said outside book projects pose potential conflicts for newspapers and their reporters.

"When a journalist has a financial interest outside the newspaper, it can call into question his reporting," Parks said.

Parks said reporters at the Times sometimes had to choose between continuing to cover a beat or leaving the beat to write a book about it.

Mason, who said he is not a victim of past clergy sexual abuse, said he got involved in the issue more than two years ago because he feels passionately about protecting children. He is a father of three.

He said he doesn't read the diocesan newspaper and termed it at best, yellow journalism, and, at worst, propaganda.

"The goal was not to bring Bill Zajac and The Republican into this," he said. "They have been the heroes in this."

Pomerleau, a journalist for 20 years, said he stands by his story.

Reporter Jack Flynn contributed to this story.